JP2010239106A - Adhesive for bonding semiconductor chip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive for bonding a semiconductor chip, a cured product of which is low in linear expansion and elastic modulus, while permitting a decrease in generating stresses exerted on a bonded semiconductor chip, to obviate the occurrence of cracks in a conductive portion, such as, solder and produce high-reliability semiconductor devices, and to provide a non-conductive paste and a non-conductive film produced through the use of the adhesive for bonding a semiconductor chip. <P>SOLUTION: The adhesive for bonding the semiconductor chip contains curable compound, curing agent and polyimide particles. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention provides a highly reliable semiconductor device that has a low linear expansion coefficient and elastic modulus of a cured product, reduces the occurrence of stress on a bonded semiconductor chip, and prevents the occurrence of cracks in conductive portions such as solder. The present invention relates to an adhesive for bonding a semiconductor chip. The present invention also relates to a non-conductive paste and a non-conductive film manufactured using the semiconductor chip bonding adhesive.

In the manufacturing method of a semiconductor device, when a semiconductor chip is bonded and fixed to a substrate or the like (flip chip bonding), for example, an adhesive such as liquid epoxy is used. The adhesive used in the flip-chip bonding process is required to have a property that does not generate stress as much as possible in a conductive portion such as a bonded semiconductor chip or a bump made of solder after bonding. This is because when a stress is generated in the semiconductor chip, the substrate and the semiconductor chip are peeled off or a crack is formed in the conductive portion, thereby causing a conduction failure of the semiconductor device.

In the process of cooling the adhesive from the temperature at which the adhesive is heat-cured, the stress on the semiconductor chip is the difference in the temperature dependence (linear expansion coefficient) of the shrinkage rate between the semiconductor chip, the cured adhesive, and the substrate, and It is considered that the elastic modulus of the cured product is a major factor and can be suppressed by lowering the linear expansion coefficient and elastic modulus of the cured adhesive product. Conventionally, in order to reduce the occurrence of stress on a semiconductor chip, a method of reducing the linear expansion coefficient of a cured product by adding a large amount of an inorganic filler to an adhesive has been used. For example, fillers such as silver powder and silica are added as essential components to the die attach paste for semiconductors disclosed in Patent Document 1 and having excellent adhesiveness, fast curability, and reliability.

In recent years, with the demand for miniaturization and high integration of semiconductor devices, the miniaturization of wiring and inter-wiring distance has progressed, and the dielectric constant is small as a wiring insulating film material used for manufacturing semiconductor chips. So-called Low-k materials are attracting attention, and conventional adhesives to which inorganic fillers are added cannot be sufficiently applied to semiconductor chips using Low-k materials.

Low-k material is used as an insulating film material for wiring in order to prevent wiring delay due to miniaturization of wiring and wiring-to-wiring distance, for example, a hard and brittle porous material made of SiOC, SiOF, etc. Therefore, when a large stress is generated in the bonded semiconductor chip, peeling is likely to occur, and a crack is likely to occur in a conductive portion such as solder. Therefore, in order to manufacture a highly reliable semiconductor device even when using a low-k material, it is necessary to strictly reduce the generation of stress on the semiconductor chip, and the cured product has a low linear expansion coefficient. There is a need for adhesives that are not only low elastic modulus. However, increasing the amount of inorganic filler added can lower the coefficient of linear expansion of the cured adhesive, but at the same time increases the modulus of elasticity, realizing a low coefficient of linear expansion and a low modulus of elasticity simultaneously. There is a need for new ways to do this.

JP 2004-172443 A

The present invention provides a highly reliable semiconductor device that has a low linear expansion coefficient and elastic modulus of a cured product, reduces the occurrence of stress on a bonded semiconductor chip, and prevents the occurrence of cracks in conductive portions such as solder. An object of the present invention is to provide an adhesive for bonding a semiconductor chip that can be manufactured. Another object of the present invention is to provide a non-conductive paste and a non-conductive film manufactured using the semiconductor chip bonding adhesive.

The present invention is a semiconductor chip bonding adhesive containing a curable compound, a curing agent, and polyimide particles.
The present invention is described in detail below.

The inventors of the present invention produce a semiconductor chip bonding adhesive having a low linear expansion coefficient and elastic modulus of a cured product by adding polyimide particles to a semiconductor chip bonding adhesive containing a curable compound and a curing agent. It can be found that when the adhesive for bonding semiconductor chips is used, the stress on the bonded semiconductor chips can be reduced, and the occurrence of cracks in conductive parts such as solder can be prevented well. The present invention has been completed.

The adhesive for bonding a semiconductor chip of the present invention contains a curable compound.
The said curable compound is not specifically limited, For example, the compound hardened | cured by reaction, such as addition polymerization, polycondensation, polyaddition, addition condensation, or ring-opening polymerization, is mentioned. Specific examples of the curable compound include urea resin, melamine resin, phenol resin, resorcinol resin, epoxy resin, acrylic resin, polyester resin, polyamide resin, polybenzimidazole resin, diallyl phthalate resin, xylene resin, alkyl -Thermosetting compounds such as benzene resin, epoxy acrylate resin, silicon resin, urethane resin and the like. Among these, an epoxy resin is preferable because the reliability and bonding strength of a semiconductor device obtained after bonding are excellent.

The epoxy resin is not particularly limited, and examples thereof include bisphenol type epoxy resins such as bisphenol A type, bisphenol F type, bisphenol AD type, and bisphenol S type, novolac type epoxy resins such as phenol novolak type and cresol novolak type, and trisphenolmethane. Aromatic epoxy resins such as triglycidyl ether, naphthalene type epoxy resins, fluorene type epoxy resins, dicyclopentadiene type epoxy resins, modified products thereof, hydrogenated products and the like can be mentioned. These epoxy resins may be used independently and 2 or more types may be used together.

When the epoxy resin is used as the curable compound, the curable compound may contain a polymer compound having a functional group capable of reacting with the epoxy resin. By containing the high molecular compound which has a functional group which can react with the said epoxy resin, the adhesive agent for semiconductor chip joining obtained has toughness, and can have the outstanding impact resistance.

The high molecular compound which has a functional group which can react with the said epoxy resin is not specifically limited, For example, the high molecular compound etc. which have an amino group, a urethane group, an imide group, a hydroxyl group, a carboxyl group, an epoxy group etc. are mentioned. Among these, a polymer compound having an epoxy group is preferable.
When the epoxy resin is used as the curable compound, the cured product of the obtained adhesive for bonding semiconductor chips exhibits excellent toughness by further containing the polymer compound having the epoxy group. That is, the obtained cured product of the semiconductor chip bonding adhesive has excellent mechanical strength, heat resistance and moisture resistance derived from the epoxy resin, and excellent toughness derived from the polymer compound having the epoxy group. By having both, high adhesion reliability and high conduction reliability can be expressed.

The polymer compound having an epoxy group is not particularly limited as long as it is a polymer compound having an epoxy group at the terminal and / or side chain (pendant position). For example, an epoxy group-containing acrylic rubber, an epoxy group-containing butadiene rubber, Examples thereof include bisphenol type high molecular weight epoxy resin, epoxy group-containing phenoxy resin, epoxy group-containing acrylic resin, epoxy group-containing urethane resin, and epoxy group-containing polyester resin. Especially, since the hardened | cured material of the adhesive agent for semiconductor chip joining which contains many epoxy groups and has the outstanding mechanical strength, heat resistance, etc., an epoxy-group-containing acrylic resin is preferable. These polymer compounds having an epoxy group may be used alone or in combination of two or more.

As the polymer compound having a functional group capable of reacting with the epoxy resin, when the polymer compound having the epoxy group, particularly the epoxy group-containing acrylic resin is used, the preferred lower limit of the weight average molecular weight is 10,000. When the weight average molecular weight is less than 10,000, the film-forming property of the obtained adhesive for bonding a semiconductor chip becomes insufficient. For example, even if the adhesive for bonding a semiconductor chip is used in the form of a film, the shape as a film is reduced. It may not be possible to hold.

When the polymer compound having an epoxy group, particularly an epoxy group-containing acrylic resin, is used as the polymer compound having a functional group capable of reacting with the epoxy resin, the preferable lower limit of the epoxy equivalent is 200, and the preferable upper limit is 1000. When the epoxy equivalent is less than 200, the cured product of the obtained adhesive for bonding a semiconductor chip may be hard and brittle. If the epoxy equivalent exceeds 1000, the mechanical strength and heat resistance of the cured product of the obtained adhesive for bonding a semiconductor chip may be insufficient.

When the adhesive for semiconductor chip bonding of the present invention contains a polymer compound having a functional group capable of reacting with the epoxy resin, the content of the polymer compound having a functional group capable of reacting with the epoxy resin is not particularly limited. However, the preferable lower limit with respect to 100 parts by weight of the epoxy resin is 1 part by weight, and the preferable upper limit is 500 parts by weight. When the content of the polymer compound having a functional group capable of reacting with the epoxy resin is less than 1 part by weight, the toughness may be insufficient and the adhesion reliability may be inferior when heat distortion occurs. When content of the high molecular compound which has a functional group which can react with the said epoxy resin exceeds 500 weight part, the heat resistance of the hardened | cured material of the adhesive agent for semiconductor chip joining obtained may fall.

The adhesive for semiconductor chip bonding of the present invention contains a curing agent.
The said hardening | curing agent is not specifically limited, For example, an amine type hardening | curing agent, an acid anhydride hardening | curing agent, a phenol type hardening | curing agent etc. are mentioned. Of these, acid anhydride curing agents are preferred.

The acid anhydride curing agent is not particularly limited, but a bifunctional acid anhydride curing agent is preferable. The bifunctional acid anhydride curing agent is not particularly limited. For example, phthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydroanhydride. Examples include phthalic acid and maleic anhydride.

Further, as the acid anhydride curing agent, trifunctional or higher functional acid anhydride curing agent particles may be used. The trifunctional or higher functional acid anhydride curing agent particles are not particularly limited. For example, particles composed of trifunctional acid anhydrides such as trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic acid anhydride, methylcyclohexene tetracarboxylic acid. Examples thereof include particles composed of tetrafunctional or higher functional acid anhydrides such as acid anhydrides and polyazeline acid anhydrides.

The average particle diameter of the trifunctional or higher functional acid anhydride curing agent particles is not particularly limited, but a preferable lower limit is 0.1 μm and a preferable upper limit is 20 μm. When the average particle diameter of the trifunctional or higher functional acid anhydride curing agent particles is less than 0.1 μm, aggregation of the curing agent particles may occur, and the resulting adhesive for bonding a semiconductor chip may be thickened. If the average particle diameter of the trifunctional or higher functional acid anhydride curing agent particles exceeds 20 μm, the curing agent particles cannot be sufficiently diffused during curing, resulting in poor curing.

Although content of the said hardening | curing agent is not specifically limited, The preferable minimum with respect to 100 weight part of said curable compounds is 5 weight part, and a preferable upper limit is 150 weight part. When the content of the curing agent is less than 5 parts by weight, the obtained adhesive for bonding a semiconductor chip may not be sufficiently cured. When content of the said hardening | curing agent exceeds 150 weight part, the connection reliability of the adhesive agent for semiconductor chip bonding obtained may fall. The content of the curing agent is more preferably 10 parts by weight and more preferably 140 parts by weight with respect to 100 parts by weight of the curable compound.

Moreover, when the said hardening | curing agent contains the said bifunctional acid anhydride hardening | curing agent and the said trifunctional or more acid anhydride hardening | curing agent particle | grain, these compounding ratios are not specifically limited, The said trifunctional or more acid anhydride Value obtained by dividing content (weight) of product curing agent particle by content (weight) of bifunctional acid anhydride curing agent [= (content of trifunctional or higher functional acid anhydride curing agent particles) / (bifunctional The preferred lower limit of the content of the acid anhydride curing agent)] is 0.1, and the preferred upper limit is 10. When the value is less than 0.1, the effect of adding the trifunctional or higher functional acid anhydride curing agent particles may not be sufficiently obtained. If the above value exceeds 10, the resulting cured product of the semiconductor chip bonding adhesive may become brittle, and sufficient adhesion reliability may not be obtained. A more preferred lower limit of the above value is 0.2, and a more preferred upper limit is 8.

The adhesive for bonding a semiconductor chip of the present invention preferably contains a curing accelerator.
The said hardening accelerator is not specifically limited, For example, an imidazole series hardening accelerator, a tertiary amine type hardening accelerator, etc. are mentioned. Of these, an imidazole-based curing accelerator is preferred because it is easy to control the reaction system for adjusting the curing speed and the physical properties of the cured product. These hardening accelerators may be used independently and 2 or more types may be used together.

The imidazole curing accelerator is not particularly limited. For example, 1-cyanoethyl-2-phenylimidazole in which the 1-position of imidazole is protected with a cyanoethyl group, or an imidazole curing accelerator with a basicity protected with isocyanuric acid (trade name) “2MA-OK”, manufactured by Shikoku Kasei Kogyo Co., Ltd.). These imidazole type hardening accelerators may be used independently and 2 or more types may be used together.

When the adhesive for semiconductor chip bonding of the present invention contains the curing accelerator, the content of the curing accelerator is not particularly limited, but the preferred lower limit for 100 parts by weight of the curable compound is 1 part by weight, and the preferred upper limit is 20 parts by weight. If the content of the curing accelerator is less than 1 part by weight, the resulting semiconductor chip bonding adhesive may not be sufficiently cured. When content of the said hardening accelerator exceeds 20 weight part, the adhesive reliability of the adhesive agent for semiconductor chip joining obtained may fall.

The adhesive for semiconductor chip bonding of the present invention contains polyimide particles.
By adding the polyimide particles, the linear expansion coefficient of the cured product of the semiconductor chip bonding adhesive can be reduced without adding an inorganic filler or the like. Furthermore, the inorganic filler has the effect of increasing the elastic modulus at the same time as decreasing the linear expansion coefficient, whereas the polyimide particles can decrease the linear expansion coefficient while suppressing an increase in the elastic modulus. Since the generation of stress on the bonded semiconductor chip can be prevented by lowering the linear expansion coefficient and elastic modulus of the cured product of the semiconductor chip bonding adhesive, the semiconductor chip bonding adhesive of the present invention can be prevented. When is used, it is possible to satisfactorily prevent the generation of stress on the bonded semiconductor chips and the generation of cracks in conductive portions such as solder.

The polyimide compound contained in the polyimide particles is not particularly limited, but a polyimide compound having an aromatic ring in the main skeleton is preferable. By having an aromatic ring in the main skeleton, the polyimide compound has a more rigid and less fluctuating molecular structure, and can further reduce the linear expansion coefficient of a cured product of the obtained adhesive for bonding a semiconductor chip.
The polyimide compound having an aromatic ring in the main skeleton is not particularly limited, and examples thereof include polyimide compounds having an aromatic ring in the main skeleton such as phenyl, biphenyl, and naphthalene. Specifically, for example, poly (N, N '-P-phenylene-biphenyltetracarboxylimide) and the like.

The minimum with preferable content of the said polyimide compound in the said polyimide particle is 10 weight%. If the content of the polyimide compound is less than 10% by weight, the effect of adding the polyimide particles may be hardly obtained, and the cured product of the obtained adhesive for bonding semiconductor chips has a sufficiently low linear expansion coefficient. And may not have an elastic modulus. The minimum with more preferable content of the said polyimide compound in the said polyimide particle is 20 weight%, and a still more preferable minimum is 50 weight%.

The average particle diameter of the polyimide particles is not particularly limited, but a preferable lower limit is 0.1 μm and a preferable upper limit is 30 μm. When the average particle size of the polyimide particles is less than 0.1 μm, the adhesive for semiconductor chip bonding tends to thicken by adding the polyimide particles, so that a sufficient amount may not be added. If the average particle diameter of the polyimide particles exceeds 30 μm, the resulting cured product of the adhesive for bonding a semiconductor chip may not sufficiently exhibit a low linear expansion. The minimum with a more preferable average particle diameter of the said polyimide particle is 0.5 micrometer, and a more preferable upper limit is 20 micrometers.

The polyimide particles are preferably surface-treated.
By applying surface treatment, it is possible to suppress the thickening of the adhesive for bonding semiconductor chips, and to add a large amount of the above polyimide particles while ensuring fluidity and wettability, and the effect of reducing the linear expansion coefficient of the cured product Can be further increased.

The surface treatment method is not particularly limited, and examples thereof include a surface treatment method using a silane coupling agent.
The method of performing the surface treatment using the silane coupling agent is not particularly limited. For example, a method of reacting a functional group present on the surface of the polyimide particle with the silane coupling agent, or forming a coating layer on the surface of the polyimide particle. Then, the method etc. with which the functional group which exists in the surface of a coating layer and a silane coupling agent are made to react are mentioned.
The method for forming the coating layer is not particularly limited, and examples thereof include a method for physically adsorbing polyvinyl alcohol.

The method for producing the polyimide particles is not particularly limited. For example, by preparing a tetracarboxylic anhydride-containing solution and a diamine compound-containing solution, mixing these solutions, and performing ultrasonic stirring, After precipitating the polyamic acid particles, the resulting polyamic acid particles are imidized to form polyimide particles. If necessary, the obtained polyimide particles are subjected to the above-described surface treatment. . According to this method, fine polyimide particles can be obtained by ultrasonic stirring.

Moreover, as a method for producing the polyimide particles, for example, a diamine compound that forms an imide structure that is soluble in a reaction solvent, a diamine compound that forms an imide structure that is insoluble in a reaction solvent, and a functional group such as an amino group. A polyamic acid varnish is prepared by reacting the diamine mixture with tetracarboxylic anhydride in a reaction solvent using a diamine mixture comprising a diamine compound that forms an imide structure having a group. The method of performing the above surface treatment with respect to the obtained polyimide particle as needed after depositing a polyimide particle from the reaction solvent by heating is also mentioned. According to this method, the polyimide particle which has a desired average particle diameter can be obtained by adjusting the compounding ratio of the diamine compound in a diamine mixture.

Furthermore, the polyimide particles can be surface-treated by improving the method for producing the polyimide particles as described above.
For example, polyimide particles having an amino group on the surface by combining a trivalent amine such as 2,4,6-triaminopyridine with two kinds of raw materials of the tetracarboxylic anhydride and the diamine compound. Is obtained. The surface of the polyimide particle can be secondarily modified by reacting this amino group with a functional compound having, for example, a glycidyl group or a carboxyl group.

Among the polyimide particles, examples of commercially available products include UIP-S, UIP-R, and the like (both manufactured by Ube Industries, Ltd.).

In the adhesive for bonding a semiconductor chip of the present invention, the content of the polyimide particles is not particularly limited, but a preferable lower limit with respect to 100 parts by weight of the curable compound is 5 parts by weight, and a preferable upper limit is 900 parts by weight. When the content of the polyimide particles is less than 5 parts by weight, the effect of adding the polyimide particles may be hardly obtained, and the cured product of the obtained adhesive for bonding semiconductor chips has a sufficiently low linear expansion coefficient. And may not have an elastic modulus. If the content of the polyimide particles exceeds 900 parts by weight, the fluidity of the obtained adhesive for bonding a semiconductor chip may be insufficient, and the wettability may not be ensured.
The content of the polyimide particles is more preferably 50 parts by weight with respect to 100 parts by weight of the curable compound, more preferably 700 parts by weight, still more preferably 100 parts by weight, and even more preferably 500 parts by weight.

The adhesive for bonding a semiconductor chip of the present invention is an inorganic filler as long as the effect of the present invention is not hindered, that is, within the range where the linear expansion coefficient of the cured product is further reduced and the elastic modulus is not increased. It may contain.
The inorganic filler is not particularly limited, and examples thereof include silica such as fumed silica and colloidal silica, glass fiber, and alumina fine particles.

When a particulate inorganic filler is used as the inorganic filler, the preferred lower limit of the average particle diameter is 0.1 nm, and the preferred upper limit is 30 μm. When the average particle size of the particulate inorganic filler is less than 0.1 nm, the thickening effect is high, and the fluidity of the resulting adhesive for bonding a semiconductor chip may be lowered. When the average particle diameter of the particulate inorganic filler exceeds 30 μm, the inorganic filler may be bitten between the electrodes when pressure bonding is performed using the obtained adhesive for bonding a semiconductor chip.

When the semiconductor chip bonding adhesive of the present invention contains the inorganic filler, the content of the inorganic filler is not particularly limited, but the preferred lower limit for 100 parts by weight of the curable compound is 5 parts by weight, and the preferred upper limit is 100 parts by weight. If the content of the inorganic filler is less than 5 parts by weight, the effect of adding the inorganic filler may be hardly obtained. If the content of the inorganic filler exceeds 100 parts by weight, the linear expansion coefficient of the cured product of the adhesive for bonding a semiconductor chip is decreased, but at the same time, the elastic modulus is increased and the stress on the bonded semiconductor chip is increased. May increase, and cracks in conductive parts such as solder may easily occur. The content of the inorganic filler is more preferably 50 parts by weight with respect to 100 parts by weight of the curable compound.

The adhesive for bonding a semiconductor chip of the present invention may contain a diluent within a range that does not impair the effects of the present invention.
Although the said diluent is not specifically limited, The reactive diluent taken in by hardened | cured material at the time of heat-hardening of the adhesive for semiconductor chip joining is preferable. Of these, a reactive diluent having two or more functional groups in one molecule is more preferable in order not to deteriorate the adhesion reliability of the obtained adhesive for bonding a semiconductor chip.
Examples of the reactive diluent having two or more functional groups in one molecule include aliphatic epoxy, ethylene oxide modified epoxy, propylene oxide modified epoxy, cyclohexane epoxy, dicyclopentadiene epoxy, phenol epoxy and the like. Can be mentioned.

When the adhesive for semiconductor chip bonding of the present invention contains the diluent, the content of the diluent is not particularly limited, but the preferred lower limit for 100 parts by weight of the curable compound is 1 part by weight, and the preferred upper limit is 50 parts by weight. Part. If the content of the diluent is less than 1 part by weight, the effect of adding the diluent may be hardly obtained. If the content of the diluent exceeds 50 parts by weight, the adhesive reliability of the obtained semiconductor chip bonding adhesive may be inferior, or the viscosity characteristics described later may not be obtained. The content of the diluent is more preferably 5 parts by weight and more preferably 20 parts by weight based on 100 parts by weight of the curable compound.

The adhesive for bonding a semiconductor chip of the present invention may contain a solvent, if necessary.
The solvent is not particularly limited, and examples thereof include aromatic hydrocarbons, chlorinated aromatic hydrocarbons, chlorinated aliphatic hydrocarbons, alcohols, esters, ethers, ketones, glycol ethers (cellosolves), and fats. Examples thereof include cyclic hydrocarbons and aliphatic hydrocarbons.

The adhesive for semiconductor chip bonding of the present invention may contain an inorganic ion exchanger, if necessary. Among the inorganic ion exchangers, examples of commercially available products include IXE series (manufactured by Toagosei Co., Ltd.).
Although content of the said inorganic ion exchanger is not specifically limited, A preferable minimum is 1 weight% and a preferable upper limit is 10 weight%.

The semiconductor chip bonding adhesive of the present invention may contain additives such as an anti-bleeding agent and an adhesion-imparting agent such as an imidazole silane coupling agent, if necessary.

The adhesive for semiconductor chip bonding of the present invention has a preferred lower limit of viscosity of 20 Pa · s and a preferred upper limit of 1000 Pa · s at 0.5 rpm when the viscosity is measured at 25 ° C. using an E-type viscometer. . When the viscosity is less than 20 Pa · s, the semiconductor chip bonding adhesive may lack shape retention. When the viscosity exceeds 1000 Pa · s, the adhesive for bonding a semiconductor chip may lack discharge stability when applied with an air dispenser.

Further, the adhesive for bonding a semiconductor chip of the present invention has a viscosity measured at 25 ° C. and 5 rpm using an E-type viscometer under conditions of T ₁ and 25 ° C. and 0.5 rpm using an E-type viscometer. the viscosity measured is taken as T _2, the lower limit of T 2 _/ T ₁ is 2, it is preferable that the upper limit is 8. When T ₂ / T ₁ is within the above range, the semiconductor chip bonding adhesive can have thixotropy suitable for application.

In the adhesive for bonding a semiconductor chip of the present invention, the preferable lower limit of the linear expansion coefficient at a temperature not higher than the glass transition temperature of a cured product obtained by curing by heating is 10 ppm, and the preferable upper limit is 60 ppm. If the linear expansion coefficient is less than 10 ppm, the linear expansion coefficient is lower than that of solder, substrate, etc., and stress may concentrate on the joint due to thermal expansion of solder, substrate, etc. May decrease. When the linear expansion coefficient exceeds 60 ppm, when strain due to heat occurs, stress on the bonded semiconductor chip increases, and cracks in conductive portions such as solder may easily occur. A more preferable lower limit of the linear expansion coefficient is 15 ppm, and a more preferable upper limit is 55 ppm.

In the adhesive for bonding a semiconductor chip of the present invention, the preferable lower limit of the linear expansion coefficient at a temperature equal to or higher than the glass transition temperature of a cured product obtained by curing by heating is 50 ppm, and the preferable upper limit is 140 ppm. A more preferable lower limit of the linear expansion coefficient is 60 ppm, and a more preferable upper limit is 130 ppm.
In this specification, the linear expansion coefficient of the cured product of the semiconductor chip bonding adhesive is a cured product having a thickness of 500 μm obtained by curing the adhesive at 110 ° C. for 40 minutes, and further at 170 ° C. for 30 minutes, Using a thermal stress strain measuring device ("EXTEAR TMA / SS 6100", manufactured by SII Nano Technology), the temperature was raised to 300 ° C with a load of 2N, a heating rate of 5 ° C / min, and a sample length of 1 cm. It is a value obtained from the slope of the obtained SS curve.

The lower limit of the elastic modulus at −55 to 125 ° C. of the cured product obtained by curing by heating of the semiconductor chip bonding adhesive of the present invention is 0.01 GPa, and the preferable upper limit is 7 GPa. When the elastic modulus is less than 0.01 GPa, the cured product of the semiconductor chip bonding adhesive may not have sufficient heat resistance. When the elastic modulus exceeds 7 GPa, when heat distortion occurs, the stress on the bonded semiconductor chip increases, and cracks in conductive parts such as solder may easily occur. The more preferable lower limit of the elastic modulus is 0.05 GPa, the more preferable upper limit is 6.5 GPa, and the more preferable upper limit is 6 GPa.
Further, the preferable lower limit of the value of (elastic modulus at −55 ° C./elastic modulus at 125 ° C.) is 1, and the preferable upper limit is 3. When the above value exceeds 3, particularly, the influence of strain due to heat increases, stress on the bonded semiconductor chip increases, and cracks in conductive portions such as solder may be more likely to occur. A more preferred lower limit of the above value is 2.
In this specification, the elastic modulus of the cured product of the adhesive for bonding a semiconductor chip is obtained by preparing a cured product having a thickness of 500 μm obtained by curing the adhesive at 110 ° C. for 40 minutes and further at 170 ° C. for 30 minutes. Using an elasticity measuring machine (model “DVA-200”, manufactured by IT Measurement & Control Co., Ltd.), the temperature was raised to 300 ° C. at a heating rate of 5 ° C./min, pulling and gripping width of 24 mm, 10 Hz, −55 ° C., 125 It is a value (GPa) obtained by measuring at ° C.

The method for producing the semiconductor chip bonding adhesive of the present invention is not particularly limited. For example, the curable compound, the curing agent and the polyimide particles, and, if necessary, the curing accelerator, the inorganic filler, A method of obtaining a semiconductor chip bonding adhesive by blending and mixing a predetermined amount of other additives and the like can be mentioned.
The method of mixing is not particularly limited, and examples thereof include a method of mixing using a homodisper, a universal mixer, a Banbury mixer, a kneader, and the like.

The use of the adhesive for bonding a semiconductor chip of the present invention is not particularly limited. For example, in manufacturing a semiconductor device, the adhesive for bonding a semiconductor chip of the present invention is used to bond and fix the semiconductor chip to a substrate or another semiconductor chip. can do. In addition, a non-conductive paste (NCP) and a non-conductive film (NCF) are manufactured using the semiconductor chip bonding adhesive of the present invention, and the semiconductor chip is formed on the substrate using the non-conductive paste and non-conductive film. Alternatively, it can be bonded and fixed to another semiconductor chip.

A non-conductive paste and a non-conductive film produced using the semiconductor chip bonding adhesive of the present invention are also one aspect of the present invention. Since the non-conductive paste and non-conductive film of the present invention are manufactured using the adhesive for bonding a semiconductor chip of the present invention, the cured product has a low coefficient of linear expansion and a low elastic modulus. By reducing the generation of the stress, it is possible to satisfactorily prevent the occurrence of cracks in the conductive part such as solder.

Although the thickness of the nonelectroconductive film of this invention is not specifically limited, A preferable minimum is 2 micrometers and a preferable upper limit is 500 micrometers. If the thickness is less than 2 μm, a smooth film may not be obtained due to the inclusion of foreign matter. When the thickness exceeds 500 μm, the solvent tends to remain, and bubbles may be generated during pressure bonding and curing.

The method for producing the non-conductive film of the present invention is not particularly limited. For example, an extrusion molding method using an extruder, a curable compound or the like is diluted with a solvent to prepare a curable composition solution, and this solution is placed on the separator. And a solvent casting method in which the solution is dried, a spin coating method in which the solution is directly applied to a wafer, and a method in which the solution is screen-printed.

According to the present invention, the linear expansion coefficient and elastic modulus of the cured product are low, and it is possible to prevent the occurrence of cracks in conductive parts such as solder by reducing the generation of stress on the bonded semiconductor chip and to have high reliability. A semiconductor chip bonding adhesive capable of manufacturing a semiconductor device can be provided. Moreover, according to this invention, the nonelectroconductive paste and nonelectroconductive film manufactured using this adhesive agent for semiconductor chip joining can be provided.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

(Examples 1-13, Comparative Examples 1-5)
According to the compositions of Tables 1, 2 and 3, the materials shown below were stirred and mixed using a homodisper to prepare a semiconductor chip bonding adhesive.

(Curable compound)
Bisphenol A type epoxy resin (trade name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.)
Bisphenol A type epoxy resin (trade name “1004AF”, manufactured by Japan Epoxy Resin Co., Ltd.)
Glycidyl group-containing acrylic resin (trade name “G-2050M”, manufactured by NOF Corporation)

(Curing agent)
Trialkyltetrahydrophthalic anhydride (trade name “YH-306”, manufactured by JER)

(Curing accelerator)
2,4-Diamino-6- [2′methylimidazoline- (1 ′)]-ethyl s-triazine isocyanuric acid adduct (trade name “2MA-OK”, manufactured by Shikoku Kasei Kogyo Co., Ltd.)

(Organic particles)
Polyimide particles (trade names “UIP-S” and “UIP-R”, manufactured by Ube Industries)
Nylon particles (trade name "Trepearl SP-500", manufactured by Toray Industries, Inc.)
Benzoguanamine particles (trade name “Eposter MS05”, manufactured by Nippon Shokubai Co., Ltd.)

(Surface-treated polyimide particles)
(Production of surface-treated polyimide particles A)
100 g of polyimide particles “UIP-S” (manufactured by Ube Industries) was added to 100 mL of a 1 wt% aqueous solution of polyvinyl alcohol while stirring. After stirring at room temperature for 2 hours, the obtained product was washed with ion-exchanged water, 100 g of methanol and 2 g of phenyltriethoxysilane were added, and the mixture was stirred at room temperature for 2 hours. Thereafter, the obtained product was washed twice with acetone and then dried under reduced pressure at room temperature for 12 hours to obtain polyimide particles A surface-treated with a silane coupling agent.

(Production of surface-treated polyimide particles B)
Surface-treated polyimide particles B were obtained in the same manner as in the production of the surface-treated polyimide particles A except that phenyltriethoxysilane was changed to dimethyldiethoxysilane.

(Production of surface-treated polyimide particles C)
Surface-treated polyimide particles C were obtained in the same manner as in the production of the surface-treated polyimide particles A except that phenyltriethoxysilane was changed to glycidoxypropyltrimethoxysilane.

(Other)
Silane coupling agent (trade name “KBM-573”, manufactured by Shin-Etsu Chemical Co., Ltd.)
Thickener (Brand name "Leosil MT-10", manufactured by Tokuyama)
Inorganic filler (silica) (trade name “SE-4000”, manufactured by Admatechs)
Solvent (Methyl ethyl ketone (MEK))

<Evaluation 1>
The following evaluation was performed using the adhesive for semiconductor chip bonding obtained in Examples 1 to 7 and Comparative Examples 1 to 5. The results are shown in Tables 1 and 2.

(1) Linear expansion coefficient About the obtained adhesive for bonding semiconductor chips, a cured product having a thickness of 500 μm cured at 110 ° C. for 40 minutes and further at 170 ° C. for 30 minutes was prepared, and a thermal stress strain measuring device (model “ EXTEAR TMA / SS 6100 ", manufactured by SII NanoTechnology Inc.), heated to 300 ° C with a load of 2N, a heating rate of 5 ° C / min, and a sample length of 1 cm. From the slope of the SS curve obtained at this time The linear expansion coefficient was determined.

(2) Elastic modulus About the obtained adhesive for bonding a semiconductor chip, a cured product having a thickness of 500 μm cured at 110 ° C. for 40 minutes and further at 170 ° C. for 30 minutes was prepared, and a viscoelasticity measuring machine (model “DVA- 200 ”, manufactured by IT Measurement & Control Co., Ltd.), temperature rise rate 5 ° C./min, tension, grip width 24 mm, temperature raised to 300 ° C. at 10 Hz, and values obtained by measuring at −55 ° C. and 125 ° C. (GPa) was defined as the elastic modulus. The temperature at the peak of Tan δ was defined as the glass transition temperature (Tg).

(3) Thermal cycle test solder ball so that it becomes a daisy chain with the metal wiring in the semiconductor chip when electrically connected via the semiconductor chip to the semiconductor chip (10 mm × 10 mm) arranged in a peripheral shape Flip chip mounting (250 ° C., 10 seconds) using the obtained semiconductor chip bonding adhesive with a 20 mm × 20 mm × 1.0 mm thick substrate (glass / epoxy type FR-4) wired with copper. 5N). The obtained laminate was subjected to 1000 cycles of a thermal cycle test at −55 ° C. to 125 ° C. (each for 10 minutes), and then an evaluation of chip-adhesive-substrate peeling and a continuity test were performed.
In addition, the said peeling evaluation and conduction | electrical_connection test were done about eight samples, and the number of the laminated bodies in which peeling and the conduction defect were seen were evaluated. About the said continuity test, what changed the conduction | electrical_connection resistance value 10% or more was made into the defect.

<Evaluation 2>
The following evaluation was performed using the adhesive for semiconductor chip bonding obtained in Examples 8 to 13. The results are shown in Table 3.

(1) Viscosity About the obtained adhesive for bonding semiconductor chips, using an E-type viscometer (VISCOMETER TV-22, manufactured by Tokai Sangyo Co., Ltd., using φ15 mm rotor), the viscosity (Pa · s) was measured.

(2) Wetting and spreading (coating stability)
About the obtained adhesive for semiconductor chip joining, application | coating stability was evaluated using the air dispenser (SHOT MASTER300, the Musashi engineering company make). At this time, the used parts were a precision nozzle (made by Musashi Engineering, inner diameter 0.3 mm), and a 10 mL syringe (made by Musashi Engineering). The discharge conditions were a discharge pressure of 0.4 MPa, a gap between the semiconductor chip and the needle of 200 μm, and a semiconductor chip bonding adhesive was applied onto the glass substrate with an aim of a discharge amount of 5 mg. Next, a glass chip (10 mm × 10 mm, thickness 100 μm) was bonded onto the applied semiconductor chip bonding adhesive, and this was placed in an oven at 80 ° C. for 1 hour.
“◎” indicates that the adhesive for bonding the semiconductor chip has spread completely in the region under the glass chip, and “○” indicates that the adhesive has spread to less than 100% and 90% or more under the glass chip. The case where it spreads to an area of less than 90% and 70% or more was evaluated as “Δ”, and the case where it expanded only to an area of less than 70% under the glass chip was evaluated as “x”.

(3) Linear expansion coefficient About the obtained adhesive for bonding a semiconductor chip, a cured product having a thickness of 500 μm cured at 110 ° C. for 40 minutes and further at 170 ° C. for 30 minutes is prepared, and a thermal stress strain measuring device (model “ EXTEAR TMA / SS 6100 ", manufactured by SII NanoTechnology Inc.), heated to 300 ° C with a load of 2N, a heating rate of 5 ° C / min, and a sample length of 1 cm. From the slope of the SS curve obtained at this time The linear expansion coefficient was determined.

(4) Elastic modulus About the obtained adhesive for bonding a semiconductor chip, a cured product having a thickness of 500 μm cured at 110 ° C. for 40 minutes and further at 170 ° C. for 30 minutes was prepared, and a viscoelasticity measuring machine (model “DVA- 200 ”, manufactured by IT Measurement & Control Co., Ltd.), temperature rise rate 5 ° C./min, tension, grip width 24 mm, temperature raised to 300 ° C. at 10 Hz, and values obtained by measuring at −55 ° C. and 125 ° C. (GPa) was defined as the elastic modulus. The temperature at the peak of Tan δ was defined as the glass transition temperature (Tg).

(5) Thermal cycle test solder balls (10 mm × 10 mm) in which solder balls are arranged in a peripheral shape and daisy chain with metal wiring in the semiconductor chip when electrically connected via the semiconductor chip Flip chip mounting (250 ° C., 10 seconds) using the obtained semiconductor chip bonding adhesive with a 20 mm × 20 mm × 1.0 mm thick substrate (glass / epoxy type FR-4) wired with copper. 5N). The obtained laminate was subjected to 1000 cycles of a thermal cycle test at −55 ° C. to 125 ° C. (each for 10 minutes), and then an evaluation of chip-adhesive-substrate peeling and a continuity test were performed.
In addition, the said peeling evaluation and conduction | electrical_connection test were done about eight samples, and the number of the laminated bodies in which peeling and the conduction defect were seen were evaluated. About the said continuity test, what changed the conduction | electrical_connection resistance value 10% or more was made into the defect.

According to the present invention, the linear expansion coefficient and elastic modulus of the cured product are low, and it is possible to prevent the occurrence of cracks in conductive parts such as solder by reducing the generation of stress on the bonded semiconductor chip and to have high reliability. A semiconductor chip bonding adhesive capable of manufacturing a semiconductor device can be provided. Moreover, according to this invention, the nonelectroconductive paste and nonelectroconductive film manufactured using this adhesive agent for semiconductor chip joining can be provided.

Claims (5)

A semiconductor chip bonding adhesive comprising a curable compound, a curing agent, and polyimide particles. The adhesive for semiconductor chip bonding according to claim 1, wherein the polyimide particles contain a polyimide compound having an aromatic ring in the main skeleton. The adhesive for semiconductor chip bonding according to claim 1, wherein the polyimide particles are surface-treated. A non-conductive paste produced using the adhesive for bonding a semiconductor chip according to claim 1, 2 or 3. A non-conductive film manufactured using the adhesive for bonding a semiconductor chip according to claim 1, 2 or 3.